E

[bernhardas]

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[kopi234]

to me the more annoying thing is seller dishonesty

[Tervueren]

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Oh well back to the seller.

[bernhardas]

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[iangreenhalgh1]

Yes, that's definitely fungus. However, it's not going to affect the image if it's just those spots.

Try the lens out, see if it performs okay for you, if so, negotiate a partial refund from the seller.

Being in Dubai, you have that very strong sun, so stick the lens in a window, the UV in the sunlight will kill the fungus, which will stop it from spreading and ruining the lens. Not sure how long I will take, I expect you have a lot of UV in Dubai.

Looks like it will be simple to clean, the spots look to be on the back of the front element. If you have the inclination, you can unscrew the name ring and take the front element out, then clean the fungus off, for those small spots, q-tips and 99% ISO alcohol should do the trick. Most likely the coating has been etched slightly by the fungus, but as it's only a few little spots, those small flaws in the coating won't spoil anything.

If you don't fancy trying to clean it yourself, you can get it cleaned, shouldn't be expensive as it's a simple job not requiring dis-assembly of the lens beyond removing the front element. If you give the lens a good sunbath to kill the fungus, you can bide your time finding somewhere to clean it as dead fungus won't spread.

[luisalegria]

UV is one thing, but avoid overheating the lens, as you can also create haze in internal elements when volatile lubricants evaporate and later condense.

[parabellumfoto]

Is it possible that the fungus grew whilst in transit? I'm curious what the more knowledgable have to say.

[iangreenhalgh1]

[gaeger]

I don't agree that such fungus doesn't have an effect. No, you won't see a shadow from spots like that on your image. But they will degrade the image, even if only slightly. If material on the inside of lenses had no effect at all on image quality, maybe manufacturers wouldn't go to such lengths to keep things clean in the manufacturing process.

Now you may decide that the amount of degradation is so small as to not affect enjoyment of the lens, but that's another thing!

[bernhardas]

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[Attila]

you can store fungused lenses mixed with healthly , try it with cheap ones, until storage is properly, low humidity, allow to get light at least minimal , healthly lens will not infect , fungus spores are everywhere in air, key is they found proper living environment or not, humid and dark what they need. So worry about only you can keep your lenses in dust free, light and dry environment or not.

http://forum.mflenses.com/storing-lenses-t812.html

[bernhardas]

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[visualopsins]

that's because everything is already infected!

Preventing growth is necessary, in any case. Even when kill all fungi using ozone, carcasses provide perfect environment for new growth, when environment permits: relative humidity above 40%. Light with UV content can sterilize any growth that begins if humidity goes above 40%.

[Braddanman]

Fungus that affects lenses is like any other plant except that instead of needing light to grow it needs darkness.
Plants need three things to grow, light, food and water.
Fungus that affects lenses needs three things to grow, darkness, food (I'm not sure exactly what in lenses, dust or the coating. Do uncoated lenses get affected?) and water, in this case from humidity.
If you keep a plant in the dark OR don't water it, it will die.
If you keep a lens with fungus in the light OR below the level of humidity it requires the fungus will die. It's simple biology. The remnants of the dead fungus will remain or the effects of it on the coating will show (etching if you're unlucky). Any dead fungus should be removed if it affects performance. A dead fungus will not regrow. New spores will germinate though, if the conditions are suitable again.
Fungus spores are everywhere and we breathe them in with every lungful of air. They are probably inside a lens as soon as it leaves the sterile conditions of a factory. It's just waiting for the right conditions to germinate which is why you shouldn't leave a lens with its caps on, in a bag or in a cupboard if the humidity is high enough.
I don't understand why manufacturers use black lens caps. Why not clear? Minolta did use clear rear lens caps on their Dynax af lenses.
If you keep a lens without it's caps on in a bright area even if in high humidity fungus will not grow.
Using your lenses regularly also helps as you keep exposing them to light.

I've worked in the Dry Rot industry and eradicating dry rot is simple, eradicate the source of water and it will die and repair only the damage that has been done. There are a lot of "specialist" contractors who will carry out very expensive and unnecessary work using dangerous chemicals because the customer doesn't understand the simple logic and are scared into getting these works carried out.

Understanding Dry Rot is simple so is lens fungus.

(NB Dry rot needs damp but not as wet as wet rot)